I had this problem before, with the original game. Is a bug of the game and/or origin, not zlorigin nor mods.
Go into my documents/the sims 4 folder and open options.ini .Look for the fullscreen option. If it's 0, set it to 1. If it's 1, set it to 0.
Now launch the game, it should work. Once in game, you can edit to windowed or fullscreen as you please, it should always work from now on.
Cheers